Sat, Oct 31, 2026
Thornton, CO
Entry is $40 now and rises to $45 after Sep 1, 2026, so registering before then saves $5.
A Halloween costume run through Thornton, timed to fall on an actual Halloween weekend. The vibe is more about what you are wearing than how fast you finish, with music along the course and seasonal snacks waiting at the end. Expect plenty of creative costumes and nobody taking the clock too seriously.
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Set a goal and get a pace band: every mile split on a card sized for your phone lock screen, so race morning needs no math.
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